Thesaurus of Geographic Names (TGN)
The TGN is one of three Getty Vocabulary Databases. It contains around 1,106,000 names and other information about places.
The focus of each TGN record is a place. There are around 912,000 places in the TGN. In the database, each place record (also called a subject) is identified by a unique numeric ID. Linked to the record for the place are names, the place's parent or position in the hierarchy, other relationships, geographic coordinates, notes, sources for the data, and place types, which are terms describing the role of the place (e.g., inhabited place and state capital). The temporal coverage of the TGN ranges from prehistory to the present and the scope is global.
Link to resource:
Thesaurus of Geographic Names (TGN)